Rotary piston pump

ABSTRACT

This invention may find use in applications such as pumps and other machines, it solves the problem of reduction of hydrodynamic resistance multiply and increases the capacity. The offered mechanim comprises of disc-shaped housing (1) with through hole (2), which is overlapped by mobile parts of rotary-piston group. Four chambers (6), formed by rotor (5) and pistons (11, 12), move in a circle inside the housing hole (2) in the plane of axle of the hole and run alternately along two sides of the housing. On running along one side they increase their volume, and along the other they reduce it, pumping over fluid through the said hole (2) in the housing. A rotary-piston group kinematically represents a modified Hooke joint. Shafts (4) are positioned at an angle. Sleeves of forks are changed into single arc-shaped half-sleeves, which are located directly on the shafts (one sleeve on each shaft). Cruciform has a spherical shape with two intersected circular canals and functionally the cruciform represents a rotor of the rotary-piston mechanism. Half-sleeves of shafts, located in the cruciform canals, functionally represent doubled pistons (11, 12). Inner surface of the through hole (2) in the housing and outer surface of members of the rotary-piston group (5, 11, 12) have spherical shape.

This application is the national phase under 35 U.S.C. §371 of prior PCTInternational Application No. PCT/EE96/00003 which has an Internationalfiling date of Dec. 13, 1996 which designated the United States ofAmerica, the entire contents of which are hereby incorporated byreference.

This invention relates to mechanical engineering and may found use inapplications such as pumps and other machines using varying-capacityworking chambers. Of the rotary-piston mechanisms with varying-capacitychambers, practical use has a Wankel mechanism. One of its disadvantagesis a need for counterbalances mounted on rotor-carrying shaft becausewhile rotating, shaft's center-of-gravity moving along the circulartrajectory.

It is known a rotary-piston mechanism (Spherical engine with rotatingpistons, Japan pat. claim No 4744565 class 51 B 61, F01 C 3100, pub. in1972) with all parts' centers-of-gravity staying motionless during thework. Structurally it is designed in the form of a housing with aspherical chamber accommodating a Hooke joint having shafts mounted atan angle with respect to each other. Cruciform of the joint is designedin the form of a disk and forks of shafts' have the form of ahalf-disks. Surfaces of the forks and the cruciform define four workingchambers with capacity changing twice per revolution. Said mechanism hasfollowing disadvantages: pairwise-parralel character of workingchambers' following with one pair of chambers' 90 degrees phase ofrotating shift relative to another and their shape, as a result of whichevery chamber's cavity extending about 180 degrees in direction ofrotation. For this cause diametrical plane of spherical chamber ofhousing where shafts' axles of symmetry are located and intersecting, atevery moment of time is threaded by cavities of two or four workingchambers. It principally limits possibilities to reduce a hydrodynamicresistance of this mechanism.

The present invention aims to reduce hydrodynamic resistance multiply.

This goal may be achieved by giving to a housing a shape of disc withthrough hole with field that is not threaded by cavities of workingchambers of rotary-piston group because its design is based on modifiedHooke joint.

In known Hooke joint each one of two cruciform's axles is connected withshaft's fork by two articulated joints. Members of articulated joint arelocated: two sleeves on each shaft's fork and two journals on the endfaces of each cruciform's axle. This rotary-piston mechanism is based onkinematic scheme of a Hooke joint. In accordance with this scheme bothcruciform's axles have one journal of articulated joint each, that arelocated in the central parts of axles' of crusiform, spatiallyintegrated and joined each with one sleeve of cruciform and said sleevesare designed as arc-shaped half-sleeves. Cruciform has spherical shape.Journals of articulated joints of axles' of said cruciformwith withshafts' has concave shape of rotating. Intersecting in two diametricallyopposite places they girdle spherical contour of the cruciform along thediametrical lines in planes that are positioned at an angle with respectto each other. Arc-shaped half-sleeves are formed by outer sphericalsurface and by inner spherical surface of rotating that repeats innerconcave surface of rotating and is complementary to it and by surface oflongitudinal section of sleeve. Cruciform and arc-shaped half-sleevesare located in through hole of disc-shaped housing and inner surface ofsaid hole has shape of spherical belt with instant or varying width.

Cruciform accommodates 4 chambers, each of them defines by one of twoconcave cruciform's surfaces of rotating; by part of concavecomplementary surface of rotating of one arc-shaped half-sleeve; bysurface of longitudinal section of another sleeve and by inner surfaceof inner spherical belt of through hole in the housing.

Character of chambers' following during the rotation is sequential andcavity of every chamber in direction of rotation extending little lessthan 90 degrees. For this reason diametrical plane of inner sphericalsurface of through hole in housing, where shafts' axles of symmetry arelocated and intersecting for four moments per revolution is not threadedby cavities of cambers of rotor-piston group because it is overlapped bymembers of rotary-piston group. If mentally substitute diametrical planeby thin disc with outer spherical surface, four moments of overlappingtransformes into four phases of overlapping per revolution ofrotor-piston group. Mentally increasing thickness of spherodisc, phasesof overlapping also increasing and linking up when width of spherodiscand width of piston became equal. Spherodisc of such thickness is notthreaded by cavities of chambers at all, and is overlapped by members ofrotary-piston group constantly. Thereby, the field of through hole ofdisc-shaped housing is not threaded by cavities of chambers ofrotary-piston group when minimal width of inner spherical belt ofthrough hole in housing is comparable with width of piston. Practically,width of disc-shaped housing may be within the limits of the piston ofrotary-piston group as well.

In the considered rotary-piston mechanism the diameter of the throughhole in a disc-shaped housing is comparable with the width of the saidhousing that causes large reducing of hydrodynamic resistance incomparison with the prototype. In accordance with technological,operational or other requirements, outer shape of the housing maydistinguish from disc.

In the FIG. 1 design of the rotary-piston mechanism for use as a pump isshown.

In the FIG. 2 a group of parts of the rotary-piston mechanism ispresented.

The offered rotary-piston mechanism comprises disc-shaped housing (1)with through hole (2), inner surface of which (3) has shape of sphericalbelt, two shafts (4) positioned at an angle with respect to each otherand directed inwards of said housing, and rotary-piston group mounted onshafts and located within of said through hole. Rotor (5) carries insidefour chambers (6) and kinematically represents a cruciform. Chambers ofsaid rotor are defined by two concave surfaces of rotating (7) and (8)that kinematically represent journals of articulated joints of two axlesof cruciform (9) and (10) with shafts. Journal (7) belongs to axle (9)of cruciform and journal (8) belongs to axle (10). Two arc-shapedhalf-sleeves (11) and (12) of two articulated joints are located on theshafts perpendicular to their axles (one sleeve on each shaft) andrepresent doubled pistons of four chambers of said rotor. Capacity ofchamber in direction of pistons' movement is limited from the side,opposed to the piston, by surface of second doubled piston (13) thatoverlaps the said chamber in the lateral direction. During the shafts'movement, each piston of the rotary-piston group is moving along thesaid chamber of the rotor, changing its capacity twice per revolution.Direction of forcing fluid through the said hole depends from thedirection of rotation of shafts of rotary-piston group.

What is claimed is:
 1. In a rotary-piston mechanism including, a housingwith a spherical chamber, accommodating a rotary-piston group,configured as a modified Hooke joint, shafts of the joint being directedtowards the interior of the housing, shafts of the joint, perpendicularto axes thereof, being mounted in sleeves with articulated joints in acruciform, having a spherical shape, parts of articulated joints of itsaxes with shafts being located in the central part of the cruciform, oneon each axis, the parts having the shape of concave surfaces of arotating girdling spherical contour of the cruciform along diametricallines in planes positioned at an angle with respect to each other andaccommodating the sleeves of the shafts, the sleeves of the shafts beingarc-shaped half-sleeves, and the cruciform functionally representing arotor of the rotary-piston mechanism, while the arc-shaped half-sleevesare double pistons of the said mechanism, the improvement comprising:thehousing being shaped as a disc, and said housing being divided into twoparts by a plane, defined by axes of the shafts.